Go for the low truck profile if you want to obtain additional stability when you do flip tricks. It also works well for small wheels. The mid-sized trucks are good for all-around use, especially in streets and parks. You can also choose the high-sized trucks that are good for carving and cruising, which is the reason why they are perfect for huge wheels.
When learning it, you will, slip and fall. Feel like an idiot doing something over and over again and not getting it, feel fear bcos you don’t know what's going to happen to you once you pop the tail, jump and slide your foot and then you land. Will you land on your board, will you be on the pavement? Will you slip out, will u kick the board away, will you land primo? No one knows but you gotta try it out and find it out yourself. Whatever it is, don't give up cos it's the strength to persevere, be crazy persistent to achieve and most of all being patient in learning and progressing that let's you earn the skateboarder title for your ownself.